O
application/octet-stream
Magic Bytes
Offset: 0
7F 45 4C 46
The O file format is an object file containing compiled machine code, typically following the Executable and Linkable Format standard originally developed by Unix System Laboratories. These files serve as intermediate products during software development, where a linker combines them with libraries to create final executable programs. Although considered safe as static data, users should only use object files from trusted sources to avoid the introduction of malicious instructions into a completed software build.
Validation Code
How to validate .o files in Python
Python
def is_o(file_path: str) -> bool:
"""Check if file is a valid O by magic bytes."""
signature = bytes([0x7F, 0x45, 0x4C, 0x46])
with open(file_path, "rb") as f:
return f.read(4) == signatureHow to validate .o files in Node.js
Node.js
function isO(buffer: Buffer): boolean {
const signature = Buffer.from([0x7F, 0x45, 0x4C, 0x46]);
return buffer.subarray(0, 4).equals(signature);
}
Go
func IsO(data []byte) bool {
signature := []byte{0x7F, 0x45, 0x4C, 0x46}
if len(data) < 4 {
return false
}
return bytes.Equal(data[:4], signature)
}API Endpoint
GET
/api/v1/o
curl https://filesignature.org/api/v1/o